• Fontan physiology underpins a venous-return–limited systemic circulation with broad organ and functional consequences. Research patterns converge on diastolic dysfunction, systemic venous return constraints, and reduced exercise capacity, alongside hepatic remodeling and adaptation across Fontan variants and conversions [8], [6], [2], [11], [9], [4].

• Imaging-driven characterization of right ventricular function in CHD relies on complementary MRI and echocardiography, with validations across TOF and Fontan anatomies guiding diagnosis, prognosis, and management [1], [3], [16], [14], [4].

• Imaging guidelines and appropriateness criteria for CHD imaging are coalescing into standard protocols for right-heart assessment in adults and single-ventricle physiology, aiming to harmonize acquisition, interpretation, and modality selection [5], [1], [13].

• Therapeutic strategies for univentricular hearts include pharmacologic management of systemic ventricular dysfunction and mechanical support via ventricular assist devices in children, reflecting a continuum of care from medical to device-based therapies [10], [7].

• Biomarkers and functional correlates of Fontan/univentricular function are explored to detect early circuit dysfunction and relate structural features to exercise capacity, with candidates such as growth differentiation factor 15 (GDF-15) emerging as early indicators [12], [8].